Substance abuse problem?

Im applying for a residency for dentistry and have been prescribed Naltrexone for alcohol dependence... to reduce cravings. They ask a question stating "have you been treated for chemical dependency or substance abuse?" Am I required to say yet? I have not been in rehab etc but I have been medically treated for it. I'd rather not put it down because I don't want to jeopardize my future or opportunities.